Counterbalance for glassware washing machines



Patented May 2, 1956 COUNTERBALANCE FOR GLASSWARE WASHING MACHINES Anders R. Lofstrand, Sr., Silver Springg Md.

Original application August 19, 1943, Serial No. 499,271. Divided and this application August 16, 1946, Serial No. 690,941

1 Claim. (01. 248-122) This invention relates to improvements in glassware washing machines and is an improvement over the washing machines embodied in prior Patents Nos. 1,992,920, issued February 26, 1935, and 2,052,835, issued September 1, 1936, and is a division of my copending application, Serial Number 499,271, filed August 19, 1943, now Patent No. 2,480,150, issued August 30, 1949.

An object of this invention is to provide an improved glassware washing machine which is designed particularly for use inwashing tumblers which are positioned in a, wire basket.

Another object of this invention is to provide a machine of this kind including a vertically movable elevator adapted to support the tumblers or glassware, the elevator being substantially balanced so as to eliminate any undue weight in the operation of the machine.

Still another object of this invention is to provide an improved means in the form of a compensating structure for compensating or equalizing the tension on the elevator, and the operating lever as the lever is rocked to lower the elevator into the desired washing compartment or to raise the elevator from the compartment.

A further object of this invention is to provide a compensating structure for use with the elevator of a dishwashing machine of the kind described which includes a spring, a flexible cord connected between the elevator and the spring v and a, difierential pulley about which the cord is trained for varying the spring tension disproportionately to the elevator travel.

With the above and other objects in view, my

invention consists in the arrangement, combination and details of construction disclosed in the drawings and specification, and then more particularly pointed out in the appended claim.

In the drawings, wherein similar reference characters designate similar parts throughout the respective views,

Figure 1 is a sectional view, partly broken away, of the elevator counterbalance constructed according to an embodiment of my invention,

Figure 2 is a detail sectional view of the lower end of the counterbalance, and

Figure 3 is a horizontal section taken on the line 33 of Figure 1.

Referring to the drawings, the numeral 5| designates generally an elevator structure movably supported relative to a horizontally shiftable carrier 29 which in turn is supported above a tub I5 by rollers engaging in the tracking 28. The elevator structure 5| includes a basket supporting frame 52 which is secured to the lower end of a depending bar 53. The supporting frame 52 is an open framebeing formed with a, basket seat 54, and a vertically disposed rear flange 55 to which the lower end of the supporting bar 53 is secured. The frame 52 is of a size to loosely engagewithin the opening 40 in the top of the tub I5 and is adapted to have positioned thereon, a wire basket 56 within which tumblers 51, disposed in an inverted position, are adapted to engage. The supporting bar 53 .is secured atits upper end by fastening members 58 to a vertically disposed block 59. The block 59 forms part of a vertically movable carriage 60. The carriage 60 includes an arcuate plate 6|, having opposed pairs of rollers 52 secured to the open side thereof. The rollers 62 movably engage in vertically disposed grooves 63, formed in the vertical elevator supporting post 54. The supporting post 54 is secured at its lower end to a rearwardly projecting boss 65 by means of set screws 65. The supporting post or standard 64 has mounted on the upper end thereof a cap 51 which is secured to the upper end of the standard or post 64 by means of a set screw 68.

A forwardly projecting plate 59 is formed integral with or secured to the cap 6'! and the plate 69 has formed integral therewith an L-shaped bracket '10. The bracket 10 includes a lower horizontal leg '11 which is downwardly ofifset by means of a connecting part 12 from the plate 69. A vertically disposed leg 13' extends upwardly from the forward end of the horizontal leg 11, and is braced by means of a web 14. The block 59, at the upper end thereof, has formed integral therewith an upwardly extending ear or lug 15 which constitutes a clamping jaw and a clamping plate 15 is adapted to confront the lug or clamping member 15, being secured in clamping position by means of fastening members 11 so as to tightly secure one end of a flexible cable 18.

The cable 18 is trained over a spirally grooved pulley 19 which is rotatably mounted on the shaft 89. The shaft is disposed between a pair of upwardly extending ears 8| secured to or formed integral with the cap 61. The cable 18 extends through an opening 82 in the plate 69 and also through an opening 83 in the cap 6'1. The cable 78 is extended downwardly into the interior of the post or standard 64 and has secured to the lower end thereof a cup-shaped slide member 84. The slide member 84 is constantly urged downwardly by means of a spring 85, which has the lower end thereof engaging against the slide member 84 and the upper end bearing against the inner side of the cap 61. The cable 18 extends downwardly through the interior of the H0 engaging the latch plate or keeper 1,23; and; further downward movement of the handle 91L forces the elevator 5| downwardly,

The movement of the cable 1-8- along the spiralgroove 19 is from the large or large r diameter of the pulley to the small end or; smaller; diame tar as the elevator 5! is being lowered in such a.

manner that the change of force on thespring 85 will be lowered with, further downward travel of the elevator 5|, in other words, the rate of change ofspring tension decreases with additional downward movement of the elevator 5lthereby providinga nearly constant forceon thecable 18 throughout the elevator travel andthe counterbalancingeffect ofthe spring ispractically constant irrespective ofthe relative position of the elevator with respect t o the support 64;

I do not mean to confine myself to the exact details of construction herein disclosed but claim all variations falling within the purview of" the appended claim.

What I desire to claim is:

In a glassware washing machine, a counterbalance structure comprising a vertical tubular support, a slide member movable on said support, a second slide member within said support, a spring engaging between said second slide member one. end of said tubularrsupport; constant- 1y urging said second slide member downwardly, a spiral grooved :pulley supported by and over the end of said tubular support, and a flexible member between said slide members trained over said pulley, that portion of the flexible member between said pulley and said first slide member terminallyengagihga larger diameter of said pulley at. a, greater distance; from the center thereof than that. portion, between the pulley and said second slidememberengaging a smaller diameter of said pulley for progressively decreasing the increase of' spring tension occasioned by the lowering of said first slide member on said support.

ANDERIS R. LQFSTRAND; SR.

fRiEFERENGES-v GIZEED 'Ifhe following references are of record in the file. of; th s pat nt;

UNITED; STATES BAiI'ENIS Number- Name- Date 1-,530,063- Tichy Mar; 17-, 1925 2;168,209 I I a-upt- Aug;v 1 1939 

